/**
 * @file
 * Generic MIB tree structures.
 *
 * @todo namespace prefixes
 */

/*
 * Copyright (c) 2006 Axon Digital Design B.V., The Netherlands.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * Author: Christiaan Simons <christiaan.simons@axon.tv>
 */

#ifndef __LWIP_SNMP_STRUCTS_H__
#define __LWIP_SNMP_STRUCTS_H__

#include "lwip/opt.h"

#if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */

#include "lwip/snmp.h"

#if SNMP_PRIVATE_MIB
	#include "private_mib.h"
#endif

#ifdef __cplusplus
extern "C" {
#endif

/* MIB object instance */
#define MIB_OBJECT_NONE 0
#define MIB_OBJECT_SCALAR 1
#define MIB_OBJECT_TAB 2

/* MIB object access */
#define MIB_OBJECT_READ_ONLY 0
#define MIB_OBJECT_READ_WRITE 1
#define MIB_OBJECT_WRITE_ONLY 2
#define MIB_OBJECT_NOT_ACCESSIBLE 3

/** object definition returned by (get_object_def)() */
struct obj_def {
	/* MIB_OBJECT_NONE (0), MIB_OBJECT_SCALAR (1), MIB_OBJECT_TAB (2) */
	u8_t instance;
	/* 0 read-only, 1 read-write, 2 write-only, 3 not-accessible */
	u8_t access;
	/* ASN type for this object */
	u8_t asn_type;
	/* value length (host length) */
	u16_t v_len;
	/* length of instance part of supplied object identifier */
	u8_t  id_inst_len;
	/* instance part of supplied object identifier */
	s32_t* id_inst_ptr;
};

struct snmp_name_ptr {
	u8_t ident_len;
	s32_t* ident;
};

/** MIB const scalar (.0) node */
#define MIB_NODE_SC 0x01
/** MIB const array node */
#define MIB_NODE_AR 0x02
/** MIB array node (mem_malloced from RAM) */
#define MIB_NODE_RA 0x03
/** MIB list root node (mem_malloced from RAM) */
#define MIB_NODE_LR 0x04
/** MIB node for external objects */
#define MIB_NODE_EX 0x05

/** node "base class" layout, the mandatory fields for a node  */
struct mib_node {
	/** returns struct obj_def for the given object identifier */
	void (*get_object_def)(u8_t ident_len, s32_t* ident, struct obj_def* od);
	/** returns object value for the given object identifier,
	   @note the caller must allocate at least len bytes for the value */
	void (*get_value)(struct obj_def* od, u16_t len, void* value);
	/** tests length and/or range BEFORE setting */
	u8_t (*set_test)(struct obj_def* od, u16_t len, void* value);
	/** sets object value, only to be called when set_test()  */
	void (*set_value)(struct obj_def* od, u16_t len, void* value);
	/** One out of MIB_NODE_AR, MIB_NODE_LR or MIB_NODE_EX */
	const u8_t node_type;
	/* array or max list length */
	const u16_t maxlength;
};

/** derived node for scalars .0 index */
typedef struct mib_node mib_scalar_node;

/** derived node, points to a fixed size const array
    of sub-identifiers plus a 'child' pointer */
struct mib_array_node {
	/* inherited "base class" members */
	void (* const get_object_def)(u8_t ident_len, s32_t* ident, struct obj_def* od);
	void (* const get_value)(struct obj_def* od, u16_t len, void* value);
	u8_t (*set_test)(struct obj_def* od, u16_t len, void* value);
	void (*set_value)(struct obj_def* od, u16_t len, void* value);

	const u8_t node_type;
	const u16_t maxlength;

	/* aditional struct members */
	const s32_t* objid;
	struct mib_node* const* nptr;
};

/** derived node, points to a fixed size mem_malloced array
    of sub-identifiers plus a 'child' pointer */
struct mib_ram_array_node {
	/* inherited "base class" members */
	void (*get_object_def)(u8_t ident_len, s32_t* ident, struct obj_def* od);
	void (*get_value)(struct obj_def* od, u16_t len, void* value);
	u8_t (*set_test)(struct obj_def* od, u16_t len, void* value);
	void (*set_value)(struct obj_def* od, u16_t len, void* value);

	u8_t node_type;
	u16_t maxlength;

	/* aditional struct members */
	s32_t* objid;
	struct mib_node** nptr;
};

struct mib_list_node {
	struct mib_list_node* prev;
	struct mib_list_node* next;
	s32_t objid;
	struct mib_node* nptr;
};

/** derived node, points to a doubly linked list
    of sub-identifiers plus a 'child' pointer */
struct mib_list_rootnode {
	/* inherited "base class" members */
	void (*get_object_def)(u8_t ident_len, s32_t* ident, struct obj_def* od);
	void (*get_value)(struct obj_def* od, u16_t len, void* value);
	u8_t (*set_test)(struct obj_def* od, u16_t len, void* value);
	void (*set_value)(struct obj_def* od, u16_t len, void* value);

	u8_t node_type;
	u16_t maxlength;

	/* aditional struct members */
	struct mib_list_node* head;
	struct mib_list_node* tail;
	/* counts list nodes in list  */
	u16_t count;
};

/** derived node, has access functions for mib object in external memory or device
    using 'tree_level' and 'idx', with a range 0 .. (level_length() - 1) */
struct mib_external_node {
	/* inherited "base class" members */
	void (*get_object_def)(u8_t ident_len, s32_t* ident, struct obj_def* od);
	void (*get_value)(struct obj_def* od, u16_t len, void* value);
	u8_t (*set_test)(struct obj_def* od, u16_t len, void* value);
	void (*set_value)(struct obj_def* od, u16_t len, void* value);

	u8_t node_type;
	u16_t maxlength;

	/* aditional struct members */
	/** points to an extenal (in memory) record of some sort of addressing
	    information, passed to and interpreted by the funtions below */
	void* addr_inf;
	/** tree levels under this node */
	u8_t tree_levels;
	/** number of objects at this level */
	u16_t (*level_length)(void* addr_inf, u8_t level);
	/** compares object sub identifier with external id
	    return zero when equal, nonzero when unequal */
	s32_t (*ident_cmp)(void* addr_inf, u8_t level, u16_t idx, s32_t sub_id);
	void (*get_objid)(void* addr_inf, u8_t level, u16_t idx, s32_t* sub_id);

	/** async Questions */
	void (*get_object_def_q)(void* addr_inf, u8_t rid, u8_t ident_len, s32_t* ident);
	void (*get_value_q)(u8_t rid, struct obj_def* od);
	void (*set_test_q)(u8_t rid, struct obj_def* od);
	void (*set_value_q)(u8_t rid, struct obj_def* od, u16_t len, void* value);
	/** async Answers */
	void (*get_object_def_a)(u8_t rid, u8_t ident_len, s32_t* ident, struct obj_def* od);
	void (*get_value_a)(u8_t rid, struct obj_def* od, u16_t len, void* value);
	u8_t (*set_test_a)(u8_t rid, struct obj_def* od, u16_t len, void* value);
	void (*set_value_a)(u8_t rid, struct obj_def* od, u16_t len, void* value);
	/** async Panic Close (agent returns error reply,
	    e.g. used for external transaction cleanup) */
	void (*get_object_def_pc)(u8_t rid, u8_t ident_len, s32_t* ident);
	void (*get_value_pc)(u8_t rid, struct obj_def* od);
	void (*set_test_pc)(u8_t rid, struct obj_def* od);
	void (*set_value_pc)(u8_t rid, struct obj_def* od);
};

/** export MIB tree from mib2.c */
extern const struct mib_array_node internet;

/** dummy function pointers for non-leaf MIB nodes from mib2.c */
void noleafs_get_object_def(u8_t ident_len, s32_t* ident, struct obj_def* od);
void noleafs_get_value(struct obj_def* od, u16_t len, void* value);
u8_t noleafs_set_test(struct obj_def* od, u16_t len, void* value);
void noleafs_set_value(struct obj_def* od, u16_t len, void* value);

void snmp_oidtoip(s32_t* ident, struct ip_addr* ip);
void snmp_iptooid(struct ip_addr* ip, s32_t* ident);
void snmp_ifindextonetif(s32_t ifindex, struct netif** netif);
void snmp_netiftoifindex(struct netif* netif, s32_t* ifidx);

struct mib_list_node* snmp_mib_ln_alloc(s32_t id);
void snmp_mib_ln_free(struct mib_list_node* ln);
struct mib_list_rootnode* snmp_mib_lrn_alloc(void);
void snmp_mib_lrn_free(struct mib_list_rootnode* lrn);

s8_t snmp_mib_node_insert(struct mib_list_rootnode* rn, s32_t objid, struct mib_list_node** insn);
s8_t snmp_mib_node_find(struct mib_list_rootnode* rn, s32_t objid, struct mib_list_node** fn);
struct mib_list_rootnode* snmp_mib_node_delete(struct mib_list_rootnode* rn, struct mib_list_node* n);

struct mib_node* snmp_search_tree(struct mib_node* node, u8_t ident_len, s32_t* ident, struct snmp_name_ptr* np);
struct mib_node* snmp_expand_tree(struct mib_node* node, u8_t ident_len, s32_t* ident, struct snmp_obj_id* oidret);
u8_t snmp_iso_prefix_tst(u8_t ident_len, s32_t* ident);
u8_t snmp_iso_prefix_expand(u8_t ident_len, s32_t* ident, struct snmp_obj_id* oidret);

#ifdef __cplusplus
}
#endif

#endif /* LWIP_SNMP */

#endif /* __LWIP_SNMP_STRUCTS_H__ */
